A planar lightwave circuit based on optical add-drop multiplexer with 16 tunable wavelength channels

An electrically controlled optical add-drop multiplexer (OADM) based on silicon on insulator is presented, which possesses 16 tunable add/drop wavelength channel of 100 GHz channel spacing. The OADM is integrated lateral p-i-n diodes with single-mode Mach-Zehnder interferometer filter, which transforms the change of refractive index induced by the plasma dispersion effect into a voltage controlled variation of add/drop wavelength. The 3dB bandwidth of add/drop wavelength is less than 0.8 nm when the etch depth, period, Bragg wavelength and length of Bragg grating are 500 nm, 223 nm, 1548.5 nm and 1000 mu m, respectively. When the applied voltage is 1.059 similar to 1.2219V, the tunable add/drop wavelength of OADM is between 1547.7 and 1536.5nm. Also, the add/drop wavelength could be controlled precisely by changing the grating period, which can satisfy the requirement of other wavelength range.